More accurate reply:
"You can use GRX 2x 48T max on this frameset, and you can use XPLR 1x 46T on this frame too, but I don't think you would be able to run 57C max tire when you use 1x 46T."
Im trying to visualise the construction of a chainstay. How would it be possible to not be able use 46t with 57C tires.